Friday, 19 July 2013

Making Coreopsis Dye from the Plant to the Wool

'Likes full sun' appears on lots of seed packets.  In January, when my grip on normal summer in Wales has slipped, I may buy them anyway. Finally, the triumph of hope over experience has paid off. Coreopsis tinctoria seeds germinated well enough indoors in March and survived potting on in freezing April conditions, with only a tiny frost watch heater in the greenhouse.  

In mid May, the plants took their chances in a newly dug over patch I fondly call 'The Dye Garden'.  It is now sheltered by a low wall, which replaces a high wooden fence that used to block much of the morning sun, with a railing facing East North East. The glorious July heat wave is really suiting my dye plants.  Below, in the foreground, the yellow flowers are Dyer's Chamomile and along the path, some transplanted and divided Rudbeckia Goldsturm have made promising clumps of leaves.  The pink cosmos were supposed to be a dye plant called Cosmos Sulphureus. Evidently, I was sold a pup there.  Still, every couple of days, I snip off all the other flower heads for drying, so at least the pink keeps a bit of colour going, along with the white lychnis that I hadn't the heart to weed out.  

In the middle ranks, some of the Coreopsis flowers are all maroon red, others red and yellow.  Lately, the dye garden has been getting a good soak with garden sprinkler every few days.  I also have some coreopsis in pots and have noticed that they are the first to wilt.  A terracotta heat wave early warning call to water the patio plants now.

Anything with tinctoria in its name will be a traditional dye plant. Woad is officially called Isatis tinctoria.  Coreopsis' common name is tickseed, there are many species apart from tinctoria.  I have read that several others will also give dye colours and all of them are native to the Americas. Word of orange in its potential colourway prompted my gamble on getting it to flower in a garden better suited to ferns.   OOOooo, fancy, a plant dye neither beige nor yellow, not even merely a greenish version of either. 
I am prepared to wait three years before the madder has grown enough roots to give me a scarlet dye, but a woman does need something to tide her over. A colour to celebrate summer heat. Coreopsis flowers are quite papery, even when fresh.  Picked on Sunday, I gave them Monday to soak in cold water. Some recipes say you can just boil them up straightaway, but I wanted maximum redness from this 30g test run.  No sign of any dye by Tuesday evening, so time to apply the heat.

These flowers got a full hour at 95 degrees Centigrade and woo, just look at the rich red in that dye bath.  As soon as it had cooled down to 40 degrees, I ladled out the flowers and put them in a cloth bag, which I returned to the pot in the interests of getting the strongest colour.  A soaked skein of wool, weighing 30g, mordanted with Alum and Cream of Tartar, was brought it slowly back up to 80 degrees over the course of an hour.  

Late at night, the bath had cooled back down and I was too impatient to leave the wool to soak overnight.  There was going to be orange!  Alkali is supposed to bring up the red in coreopsis, so the skein was dangled half way into a pan with dissolved soda ash for 20 minutes before rinsing.

Wednesday, the wool was dry and ready to be admired. The alkali end was a markedly richer colour.  Dried and wound on a niddy noddy to make a new skein, the mixed shades have all the glow of a valedictory sun, dropping to the western horizon. Embers of a long hot day.
Since the afterbath still looked reddish, I put in a whole 40g skein and simmered again.  
Not nearly so dramatic a colour, but the wet wool had a definite yellowy brown, as seen in the mid section.  Acid is supposed to bring out the yellow in coreopsis, so this skein had the left hand end dipped for 20 minutes in cold water with a large slug of white vinegar.  The brightening effect was weak.  I wondered if this might be because of too little dye per gram of wool.  Dipped the right hand end in alkali and almost instantly, the red jumped up.

By Thursday, the wool was all dried and wound ready for a final assessment.  Oh yes, Coreopsis likes full sun, soaks it up and gives it back.  

Every couple of evenings, I am picking all the flowers that have opened fully.  Though I could wait for them to fade, by next morning, plenty of new buds will already have opened, so the border is never bare for long.  Hopefully, leaving none to go to seed should prompt the plants to keep flowering for a long while, just like sweet peas.  They are so delicate, poised on their thin stalks, I fear one day of rain and wind would have them down.
The current dry heat dessicates and shrivels the picked flowerheads in no time.  Little is left of their sunray petals.  Storage space will not be an issue, no matter how many weeks of flowers are still to come.  Just got to trust that the orange will still be there, when they get soaked and simmered for dye projects next winter.  

Maybe I'll celebrate Sol Invictus with this souvenir of high summer.  It would certainly be more fun than the usual panic shopping of 20th December.


  1. Gorgeous flowers, gorgeous wool colour!

  2. Thanks. There are hundreds more in bloom today - lovely generous plant!

  3. Brilliant pictures of the wool with their flowers! I'm sure you can't wait to knit this!

  4. It will be Christmas before I have spun enough wool to make anything of substance. I'll see how many flowers I get, but I think there might not be enough for more than an accent colour. You're right though - really looking forward to it.

  5. Thanks for the info. I tried the soda ash soak - that's an amazing trick! But how do you get the color to set? It seems that it just keeps getting lighter :-(

    1. Not sure what is happening with your soda ash soak. Half a teaspoon, dissolved in hot water and added to a bowl of cold water, with wool dipped for 20 minutes then rinsed in plain water, made my coreopsis dyed wool a darker orange/red. I just had a look at the skein, which hasn't yet got knitted, and the colour has stayed like the original photo. What was your wool mordanted with before dyeing?